Abstract
Large-scale PreK programs for children from low-income families are frequently justified on findings from two single-site randomized controlled trials (RCTs) - the Perry Preschool Project and the Abecedarian Project. These programs both documented cognitive benefits during PreK participation and later reductions in grade retention and special education placement as well as multiple benefits that extended into adulthood. This paper provides a description of a statewide program in the United States that adopted many key components of the Abecedarian Project and engaged its scientific leadership in a partnership of research and program implementation. We describe the program, its scale-up, and the creation of a novel same-school longitudinal comparison group from four successive cohorts of children from low-income families totaling 15,554 public pre-K families (PPK) and 48,985 classroom peers from low-income matched families who had No Public Pre-K (NPPK). Hierarchical linear modeling revealed that PPK compared to NPPK was associated with significantly higher 3rd grade academic achievement scores in four domains (language, math, science, and social studies) as well as markedly lower rates of grade retention and special education placement, indicators of improved school health. These results were essentially replicated in each of the four successive cohorts. Further sensitivity analyses confirmed significant positive and enduring benefits for boys and girls as well as children whose parents designated their child Black, White, or Hispanic. Features of the successful implementation are identified as guideposts for other large-scale programs seeking to achieve measurable and enduring PPK benefits.